What are the current guidelines for colon cancer screening frequency?

Colorectal Cancer Screening Frequency Guidelines

For average-risk individuals, colorectal cancer screening should begin at age 45 with specific screening intervals based on the chosen test: colonoscopy every 10 years, annual FIT, CT colonography every 5 years, FIT-fecal DNA every 3 years, or flexible sigmoidoscopy every 5 years. 1, 2

Age to Begin and End Screening

Starting Age

• Age 45: Screening should begin at age 45 for all average-risk individuals 1, 2
  • This is a qualified recommendation from the American Cancer Society (ACS)
  • The U.S. Multi-Society Task Force on Colorectal Cancer (MSTF) also recommends starting at age 45 2, 3
  • This recommendation is based on increasing CRC incidence in younger populations

Special Populations

• African Americans: Some earlier guidelines suggested screening at age 45 for African Americans even when general population screening began at 50 1
• Family History: For individuals with a first-degree relative diagnosed with CRC before age 60, screening should begin at age 40 or 10 years before the youngest affected relative's diagnosis (whichever is earlier) 2, 4

Ending Age

• Age 75: Continue screening through age 75 for those in good health with life expectancy >10 years 1
• Ages 76-85: Individualize screening decisions based on prior screening history, life expectancy, health status, and patient preferences 1, 2
• After Age 85: Discontinue screening 1, 2

Recommended Screening Tests and Intervals

Tier 1 Tests (Preferred Options) 4

• Colonoscopy every 10 years

  • Most effective at detecting both cancer and precancerous polyps
  • Allows for immediate removal of polyps
  • Requires bowel preparation and sedation

• Annual FIT (Fecal Immunochemical Test)

  • High sensitivity (73.8%) for detecting cancer 2
  • No bowel preparation required
  • Must be performed yearly to maintain effectiveness

Tier 2 Tests

• CT colonography every 5 years 1
• FIT-fecal DNA test (Cologuard) every 3 years 1, 2
  • Higher sensitivity for CRC (92.3%) than FIT alone 2
  • Higher sensitivity for advanced precancerous lesions (42.4%) than FIT alone 2
• Flexible sigmoidoscopy every 5 years 1

Tier 3 Tests

• Capsule colonoscopy every 5 years (limited evidence) 2, 4

Follow-up After Screening

Normal Results

• Normal colonoscopy: Repeat in 10 years 2
• Normal FIT: Repeat annually 1
• Normal CT colonography: Repeat in 5 years 1

Abnormal Results

• Positive stool-based test: Follow up with timely colonoscopy 1
• Adenomatous polyps found and removed:
  • Large (>1 cm) or multiple adenomas: Colonoscopy in 3 years 2
  • Single small tubular adenoma: Colonoscopy in 5 years 2

Special Considerations

High-Risk Individuals

• Personal history of CRC: Surveillance colonoscopy within 1 year of resection, then every 3-5 years if normal 2
• Family history of CRC or advanced adenoma: Colonoscopy every 5 years starting at age 40 or 10 years before youngest affected relative's diagnosis 4
• Inflammatory bowel disease: More intensive surveillance recommended 1

Test Selection Factors

• Patient preference is important for adherence to screening protocols 1
• Access to high-quality screening options and follow-up colonoscopy must be considered 1
• Annual adherence to stool-based tests is crucial for effectiveness 1

Recent Evidence

Recent clinical trials show that default mailed FIT outreach achieves higher screening rates (26.2%) compared to active choice interventions in adults aged 45-49 years 5. This suggests that healthcare systems should consider systematic outreach programs to maximize screening uptake in newly eligible younger adults.

The most recent systematic review of international guidelines confirms the trend toward starting screening at age 45 for average-risk individuals and age 40 for those with a positive family history 6.